Virtual reality (VR) typically refers to computer technologies that use virtual reality headsets to generate the realistic images, sounds and other sensations that replicate a real environment or create an imaginary setting. VR also simulates a user's physical presence in this environment. VR has been defined as "a realistic and immersive simulation of a three-dimensional 360-degree environment, created using interactive software and hardware, and experienced or controlled by movement of the body" or as an "immersive, interactive experience generated by a computer".